The invention relates generally to measurement of distances between portions of hard tissue, for example, the percutaneous measurement of such distances.
Known surgical procedures exist in which information about the size of a particular opening or the distance between adjacent bones is obtained. For example, procedures are performed on joints such as the knee, shoulder, spine, etc. in which a device is placed between adjacent bones. Knowing the size of the opening or the space between the bones in which the device is to be placed prior to placement allows the surgeon to select the proper size of the material beforehand. This can reduce or prevent unnecessary trial and error during the placement portion of the procedure.
Known surgical procedures measure space between bones by using, for example, trial “spacers” of various sizes. Multiple spacers are tested in the space until the correct size is identified. Such tests with trial spacers are done using an open surgical approach to allow access to the joint. As with any open surgical procedure, however, the healing process is longer and the risk of injury and/or infection increases dramatically.
Thus, a need exists for improvements in the measurement of inter-bone spaces.